The present invention generally relates to microelectronic integrated circuits. More particularly, the present invention relates to microelectronic power regulation circuits.
Regulators are often employed to provide a desired, regulated power to microelectronic devices such as microprocessors. For example, switching regulators such as buck regulators are often used to step down a voltage (e.g., from about 3.3 volts) and provide suitable power to a microprocessor (e.g., about 10-30 amps at about 2-3 volts).
To increase speed and reduce costs associated with microprocessors, microprocessor gate counts and integration generally increase, while the size of the microprocessor per gate generally decreases. As gate counts, speed, and integration of microprocessors increase, supplying requisite power to microprocessors becomes increasingly problematic. For example, a current required to drive the processors generally increases as the number of processor gates increases. Moreover, as the gate count increases per surface area of a processor, the operating voltage of the processor must typically decrease to, among other reasons, reduce overall power consumption of the processor.
As microprocessor power demands increase, use of typical power regulators to control and supply requisite power becomes increasingly problematic. For example, the regulator may consume a relatively large amount of power during operation. This power consumption may be problematic in several regards. For example, such power consumption reduces an amount of power transmitted through the regulator to the microprocessor. Further, any heat generated by the regulator""s consumption of power must be dissipated and subtracts from a thermal budget allotted to the microprocessor. Accordingly, improved power regulators suitable for regulating high current, which dissipate relatively little power are desired.
The present invention provides improved apparatus and techniques for regulating power to a microelectronic device. More particularly, the invention provides improved devices and methods suitable for supplying electronic devices with relatively high, regulated current, with relatively little power loss.
The way in which the present invention addresses the deficiencies of now-known regulators and power supply systems is discussed in greater detail below. However, in general, the present invention provides an additional voltage source to operate a pass transistor of a linear regulator close to its saturation point. This allows the regulator to run more efficiently and thus consume less power during operation.
In accordance with one exemplary embodiment of the present invention, a regulator includes an error amplifier, a transistor, a compensation network, a reference voltage source, a supplemental voltage source, an input voltage terminal, an output voltage terminal, and a Schottky clamp.